The Effect of X-ray Irradiation on Melanocytes in the Skin*

Journal Article · Wed May 01 04:00:00 EDT 1963 · Journal of Investigative Dermatology

DOI:https://doi.org/10.1038/jid.1963.43· OSTI ID:4135833

Snell, R. S.

X-ray effects on melanocytes and melanin in the skin of the anterior abdoriinal wall were studied in black and in red male guinea pigs, at doses too low to cause erythema and other inflammatory responses. The 50-kv x rays were administered to give a surface dose of 500 rad in 0.07 min, in three sessions at weekly intervals. Biopsy skin specimens were removed 12 to 19 days following the last session. Irradiation resulted in a considerable increase in the amount of melanin present, both inside and outside melanocytes. This was accomplished by an enlargement of the pigment cell size and an increase in the length, width, and complexity of its dendritic processes. There was also a marked increase in melanocyte numbers. The increased melanogenesis was slightly less in skin specimens removed 19 days after the last irradiation, compared with those removed 12 days after treatment. Vertical sections of skin showed a considerable rise in the amount of melanin present in all layers of epidermis. An occasional flattened pigment-containing high-level branched cell was seen and large numbers of dermal melanophores packed with melanin granules were noted postirradiation. The rise in melanocyte count could be explained on the basis that mitotic division had taken place, or it is possible that amelanotic dopa-negative melanocytes are normally present in all the basal layer of the epidermis and were stimulated into activity by the x rays. In some guinea pigs, no melanocytes were seen in the control specimen, but after irradiation large numbers were present. Increased intracellular melanin suggests an increased cytocrine activity of the melanocytes following x rays. It is also suggested that following irradiation the upward movement of the melanocytes to the surface from the basal layer, which is their natural fate, is so rapid that they have insufficient time to discharge all their melanin and are thus found high up in the epidermis. (BBB)

• Research Organization: Univ. of Durham, Newcastle-upon-Tyne, Eng.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-005053
• OSTI ID: 4135833
• Journal Information: Journal of Investigative Dermatology, Journal Name: Journal of Investigative Dermatology Journal Issue: 5 Vol. 40; ISSN 0022-202X
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABDOMEN
BIOLOGY AND MEDICINE
CYTOLOGY
DISTRIBUTION
ENERGY
ERYTHEMA
GUINEA PIGS
MELANIN
MELANOCYTES
MITOSIS
PHYSIOLOGY
PIGMENTS
QUANTITY RATIO
RADIATION DOSES
RADIATION EFFECTS
SKIN
SURFACES
X RADIATION